Pump-out section for a detergent solution

ABSTRACT

A device for pumping out lye  5  for a washing machine  4  having a washing drum  6,  a lye pump  24  and a return flow container  30  arranged in the course of the pumping-out device for filling the drain area in the lye container  2  is to be presented in a cost-effective and easy-to assemble manner. 
     To this end, a lower pumping-out connecting element  25,  the return flow tank  30  and an upper pumping-out connecting element  26  is designed in one piece as an at least partially flexible tube  17,  which is guided at least partially through a tube holding device  1.

The invention relates to a device for pumping out lye having a return flow tank, the volume of which is measured such that with the lye pump off, a predefined quantity of lye can flow back through the lye pump below the washing drum under gravity and having a lower pumping-out connecting element and an upper pumping-out connecting element.

DE 35 06 761 C2 and DE 100 58 413 A1 disclose a washing machine of this type with a device for pumping out lye, which comprises a lower pumping-out connecting element connected to the pressure side of the lye pump, an upper pumping-out connecting element which can be connected for instance to an outflow and an interposed return flow tank. The return flow tank is manufactured in two pieces in DE 35 06 761 C2 and in one piece in DE 100 58 413 A1. The pumping-out connecting element and the return flow tank are connected to one another using conventional means such as a pipe coupling etc. The volume of the device for pumping out lye is measured such that with the lye pump off, a predefined quantity of lye can flow out of the device for pumping out lye back through the lye pump below the washing drum under gravity. This can take place by means of a simple backflow of the lye, but also by the back-flowing lye introducing a valve ball of the drain hose into a sealing seat for instance.

With the known devices for pumping out lye, it is disadvantageous that the manufacture and assembly are comparatively costly.

It is thus the object of the present invention to provide a cost-effective and easily installable device for pumping out lye.

This object is achieved with a device for pumping out lye as described in the introduction by means of the characterizing features of claim 1. Advantageous embodiments can be inferred from the dependent claims. Their features can be combined individually or in combination with one another and with those of claim 1.

The device for pumping out lye in the washing machine comprises at least one return flow tank as well as a lower and an upper pumping-out connecting element. The volume of the device for pumping out lye is measured such that with the lye pump off, a predefined quantity of lye can flow back through the lye pump below the washing drum under gravity, if necessary with the use of a return flow valve. The lower pumping-out connecting element, the return flow tank and the upper pumping-out connecting element are designed in one piece or seamlessly in the form of at least one partially flexible tube, with the tube being routed at least partially through a tube holding device, i.e. molded and/or fixed. In a minimal design, the device for pumping out lye thus only has two parts, namely the tube and tube holding device. In general, the device for pumping out lye only needs to fulfill the functions of the known return flow tank and the pumping-out connecting element in respect of the lye backflow. It does not need to recreate the form of the known device for pumping out lye. The function of the return flow tank and the pumping-out connecting element(s) can thus also be combined in a tube section.

The provision of the inventive device for pumping out lye firstly simplifies and reduces costs involved in the manufacture, secondly facilitates the assembly and thirdly increases reliability.

In an advantageous embodiment of the device for pumping out lye, at least one intermediate part is integrated in the tube, particularly if the intermediate part takes the form of a smooth connection with a ventilation hole. The connection is expediently so short, that the flexibility of the tube in the region of the tube holding device and/or its assembly is not noticeably restricted. The device for pumping out lye can however also comprise several intermediate parts, e.g. a further connection having a ventilation facility, e.g. for attaching sensors such as pressure or fluid sensors.

It is a particularly advantageous embodiment if the device for pumping out lye features a tube holding device, which has a sealing area comprising a preferably cylindrical and/or annular tube feedthrough in the horizontal cross-section which is inserted therein as well as a connection attached thereto, and if the smooth connection can be introduced into the tube feedthrough of the sealing area of the tube holding device in a sealed manner. The outer shape of the sealing area is not established.

The smooth connection in the sealing area is favorably sealed by means of sealing elements such as O-rings, particularly if the connection is restricted on both sides by the O-rings.

It is advantageous for effective ventilation if the ventilation hole can be positioned accurately in the region of the connection. This can be assisted for instance by means of guide elements, such as rails, grooves for example etc.

The tube can advantageously be fixed in the sealing area.

The inner volume of the tube can generally be designed in a simple manner such that the volume corresponding to the known device for pumping out lye is adjusted over the length or the internal diameter of the tube for instance.

If is favorable if the tube is at least partially a corrugated tube, preferably made out of plastic, in particular polypropylene.

It is advantageous for a safe assembly and improved operational reliability, inter alia also a primary clamp trap, if the internal diameter of the tube is dimensioned differently and/or variably, particularly if it has an enlarged diameter in the connection region to the washing machine.

Advantageously, the tube holding device has a first straight subarea facing the device connection, said first straight subarea merging via a curved area into a second straight subarea which runs perpendicular to the first straight subarea. The sealing area is favorably integrated in the second straight subarea.

In the case of a device mounted on the washing machine, it can be advantageous for volume enlargements if the tube can be positioned in a circular or arched manner in the connection region to the device and comprises a corresponding length.

In the following exemplary embodiments, the device for pumping out lye is described schematically in more detail, in which;

FIG. 1 shows a schematic representation of a vertical section of a washing machine with a device for pumping out lye,

FIG. 2 shows a perspective view of a tube holding device,

FIG. 3 shows a further perspective view of the tube holding device,

FIG. 4 shows a perspective view of a device for pumping out lye with the tube holding device from FIGS. 2 and 3 and with a suitable tube and

FIG. 5 shows a side view of a section from the tube according to FIG. 4.

In a drum-shaped lye container 2 surrounded by the machine housing 14 of the washing machine 4 shown in FIG. 1 according to the prior art, a washing drum 6 is mounted in a rotatable fashion about a horizontal axis. Water can be fed to the lye container 2 by way of a line 8, a magnetic valve 10 and a detergent feed facility 12. The maximum water level 16 that can be reached in the lye container 2 is illustrated schematically using a dashed line. A discharge line 20 is connected to the base 18 of the lye container 2, said discharge line running past a fluff filter 22 to the intake side of a lye pump 24. A drain hose 25, 26 is connected to the pressure side of the lye pump 24, said drain pump consisting of a lower pumping-out connecting element 25 and an upper pumping-out connecting element 26, which are connected with one another by way of a return flow tank 30, with the two pumping-out connecting elements being flexible and preferably being so-called corrugated tubes. The upper pumping-out connecting element 26 can be connected to an outflow or can be attached to a water outflow reservoir 28.

The volume of the return flow tank 30 is dimensioned such that after pumping out lye, if the lye pump 24 is stopped, the lye flowing back out of the drain hose 25, 26 and the return flow tank 30 through the lye pump 24 comes to rest at a level which is somewhat higher than the base area 18 of the lye container 2. This ensures that if detergent is subsequently added from the detergent feed facility 12, this detergent does not disappear in the discharge line 20 on the base 18 of the lye container 2, but is instead fed by water from the water line 8 which also has to be introduced into the washing drum 6 again.

FIG. 2 shows a slanted perspective of a tube holding device 1. This has a first straight subarea 9 directed downwards in the direction of the YO axis, said subarea 9 merging via a curved region in a second straight subarea 11, which lies perpendicular to the first straight subarea in the direction of the ZO axis. A cylindrical and/or annular sealing area 13 in the horizontal cross-section is integrated into the second straight subarea 11, said sealing area 13 having a connection 3 attached to the side. The tube holding device 1 is provided with through holes for improved installability, weight and cost savings and is open on the side outside the sealing area 13. Retainers and/or installation aids 15 are also integrated into the sealing area 13.

FIG. 3 shows the same tube holder device 1 (FIG. 1) in another view, which emerges from the axis of coordinates.

In a view similar to that of FIG. 3, FIG. 4 shows a device for pumping out lye 5 having a tube holding device 1 and a tube 17 guided therein. This device for pumping out lye 5 replaces said device known from the prior art and referred to in FIG. 1 with 25, 26, 30. The lower opening 19 is provided to allow a connection to the pressure side of the lye pump 24 of a washing machine, the upper opening 21 is intended for a connection to the outlet, e.g. to an outflow 28 (FIG. 1).

FIG. 5 shows a sketch of a section of the tube 17 associated with the sealing area 13. The tube 18 essentially consists of corrugated tube segments made out of polypropylene (PP). A smooth, cylindrical or connection-like section is integrated into the tube 17 as a ventilation facility 27. For improved perceptibility of the details of the tube design in the sealing area 13, this part of the tube is detached from the overall length of the tube 17 and is illustrated larger than the remaining parts of the tube 17. At an axial distance from a ventilation hole 29, which, in the assembled state, is positioned below the connection 3 of the tube holding device 1, sealing O-rings 23 are attached to the exterior of the ventilation facility 27. Upon insertion of the tube 17 into the sealing area 13 of the tube holding device 1, the O-rings 23 axially seal the internal annular sealing area 13 on the ventilation facility 27 and thus the connections 3. The ventilation hole 29 is ideally positioned in front of the connection 3, this being possible for instance by means of corresponding guides. Nevertheless, provided the annular area at the level of the ventilation hole 29 is at a sufficient distance from the internal wall of the tube holding device 1, positioning of the ventilation hole 28 precisely opposite the input of the connection 3 is not necessary.

In the sealing area 13 of the tube holding device 1, the tube 17 is provided with the ventilation facility 27 of the tube 17 which is sealed in the axial direction (see also FIG. 5.) The seal (here O-rings 23) ensures that liquid lye or lye steam running out of the tube 17 through the ventilation facility 27 can be drained through connection 3 and a ventilation tube (FIG. 4) disposed in a sealed manner thereupon, and does not escape into the environment at the open ends of the sealing area 13.

In the sealing area 13, the tube 17 is logically fixed to the tube holding device 1, e.g. by means of a pressure connection by way of the O-rings 23, or however by means of other methods such as adhesive, catch mechanisms, screws etc.

In the region of the lower opening 19, it is advantageous for providing an adequate liquid volume and for the function as a collection container and/or primary clamp trap, if the internal diameter of the tube 17 is comparatively enlarged there.

During connection to a washing machine, the tube 17 can expediently be so long that it is positioned in the area of the device connection in an arc, so that this arc creates additional volume. An enlargement of the internal diameter can simultaneously create more volume in this area.

The length of the tube 17 can be adjusted as needed.

In general, the device for pumping out lye 5 can be adapted to the structural conditions, e.g. as a result of varying the shape, diameter, length, material etc. 

1-7. (canceled)
 8. A washing machine comprising: a lye pump; a washing drum; a device for pumping out lye having a volume that accommodates a predefined quantity of lye to flow back through the lye pump below the washing drum under gravity when the lye pump is off; a return flow tank in a course of the device for pumping out lye, the device for pumping out lye comprising: a lower pumping-out connecting element; an upper pumping-out connecting element, wherein the lower pumping-out element, the return flow tank, and the upper pumping-out connecting element comprises a one piece flexible tube; a tube holding device through which the one piece flexible tube is guided; and a sealing area having a preferably cylindrical tube feedthrough inserted therein as well as a connection attached thereto which provides a smooth connection of the one piece flexible tube in the tube feedthrough in a sealed manner.
 9. The washing machine of claim 8, wherein the one piece flexible tube comprises an integral intermediate part comprising a smooth connection with a ventilation hole.
 10. The washing machine of claim 9, wherein the ventilation hole is located precisely in a region of a port of the connection.
 11. The washing machine of claim 10, wherein the tube is fixed in the sealing area.
 12. The washing machine of claim 8, wherein the tube comprises a polypropylene corrugated tube.
 13. The washing machine of claim 8, wherein the tube has a differently dimensioned internal diameter, in particular an enlarged diameter at the connection region on the device side.
 14. The washing machine of claim 8, wherein the tube holding device comprises a first straight subarea facing the connection region on the device side, said first straight subarea merging via a curved area into a second subarea in the course of a drain area, said second straight subarea lying perpendicular to the first straight subarea. 